Movable seat back

Claim 1

STRUCTURE FOR SUPPORTING A POSITIONABLE BACK ON A BASE FOR TILTING MOVEMENT REARWARD FROM A NORMAL POSITION ABOUT ONE AXIS AND FORWARDLY FROM A NORMAL POSITION ABOUT ANOTHER AXIS, SAID BASE PIVOTALLY SUPPORTING ONE SIDE OF SAID POSITIONABLE BACK AT A SINGLE PIVOT, SAID BASE PIVOTALLY SUPPORTING THE OPPOSITE SIDE OF SAID POSITIONABLE BACK AT FIRST AND SECOND SELECTIVE PIVOTS THEREBY DEFINING DUAL PIVOT AXES EACH BEING COMMON TO SAID SINGLE PIVOT AT SAID ONE SIDE, SAID FIRST PIVOT AND SAID SINGLE PIVOT DEFINING THE AXIS ABOUT WHICH SAID BACK IS TILTED REARWARDLY AND SAID SECOND PIVOT AND SAID SINGLE PIVOT DEFINING THE AXIS ABOUT WHICH SAID BACK IS TILTED FORWARDLY, SAID FIRST AND SECOND PIVOTS BEING DISPOSED ON A SIDE MEMBER OF SAID BASE AND COOPERATIVELY RECEIVING FIRST AND SECOND PIN MEANS RESPECTIVELY OF SAID BACK, A FIRST ARCUATE GUIDE ARCUATE GUIDE SURFACE DISPOSED ADPIVOT AND A SECOND ARCUATE GUIDE SURFACE DISPOSED ADJACENT SAID SECOND PIVOT, SAID FIRST PIN MEANS PIVOTING IN SAID FIRST PIVOT AND SAID SECOND PIN MEANS TRAVELING ALONG SAID SECOND ARCUATE GUIDE FOR STABILIZING SAID BACK AT IT IS MOVED REARWARDLY FROM A NORMAL POSITION, SAID SECOND PIN MEANS PIVOTING IN SAID SECOND PIVOT AND SAID FIRST PIN MEANS TRAVELING ALONG SAID FIRST ARCUATE GUIDE FOR STABILIZING SAID BACK AT IT IS MOVED FORWARDLY FROM A NORMAL POSITION.